1. Field of the Invention
The present invention relates to a thermoplastic resin composition that provides a molded article having a high specific gravity and an excellent flexibility, and molded articles obtained by using the composition.
2. Description of the Related Art
Polymer materials are easy to process and excellent in corrosion resistance, compared with metallic materials. In addition, polymer materials are light and comparatively inexpensive, and have excellent insulation properties, so that they recently have been used widely in many fields as raw materials or structural materials for electrical and electronic parts, machine parts, precision parts, general industrial parts and the like.
Moreover, polymer materials are excellent in processability, compared with metallic materials that require a cutting process, a sintering process or the like. In particular, when molded by injection molding, articles having a complex shape advantageously can be molded by only one process.
Regarding a balance weight mounted on a wheel in order to adjust a wheel balance of an automobile or the like, it is preferable that the balance weight is as small as possible so as not to spoil the appearance of the wheel. It is also desirable that the balance weight is easy to shape so as to fit the rim diameter of the wheel. Conventionally, as a material that satisfies these conditions, lead, which is a metallic material having a high specific gravity and an excellent flexibility, has been used as a material for forming the balance weight.
However, lead is toxic, and moreover, lead that has entered a human body from the skin and deposited in bones is very difficult to discharge and accumulates in the body. If lead is accumulated in a human body, lead poisoning may occur. Therefore, it is preferable to use a material other than lead to form the balance weight for a wheel as described above. However, at present, there is no such material having a high specific gravity and an appropriate flexibility as lead.